The invention relates to a method of shaping plastics material pre-forms into plastics material containers, in which the plastics material pre-forms are expanded inside a blow mould with the aid of an expansion agent and a stretch rod to form the plastics material containers and in which at least the blow mould and/or the stretch rod is or are sterilized if necessary at least in part with sterilization agent.
The invention further relates to an apparatus for shaping plastics material pre-forms into plastics material containers, with at least one blow moulding device comprising a blow mould and a stretch rod, and with a sterilization device and/or cleaning device, by means of which the blow moulding device is capable of being sterilized and/or cleaned at least in part.
In the following, in order to simplify the language in part only the term “sterilization” will be used instead of “sterilization and/or cleaning”. It is pointed out, however, that this term should likewise relate to a cleaning or at least a disinfection in part. This also applies in a corresponding manner to terms which contain the component “sterilization” such as for example “sterilization agent” or “sterilization device”.
Generic methods and apparatus for shaping plastics material pre-forms into plastics material containers are well known from the prior art. As well as the actual blow moulding procedure, in particular a proper sterilization of the components of a blow moulding device on a blow moulding station is also crucially important since during the production of the plastics material containers these components frequently come into contact themselves, even if only locally, with these plastics material pre-forms and/or plastics material containers. In particular, in the case of foodstuffs, such as for example fruit juices and so forth, which are susceptible to germs, spores or the like, sterile tools are crucially important and for this reason individual process steps are also frequently carried out under aseptic conditions in a clean room.
A plurality of different devices, different methods and process variants have already been developed for sterilization purposes, in order to treat not only the plastics material pre-forms and the plastics material containers but, in addition, also individual components of the respective blow moulding device with suitable sterilization agents, such as for example ozone (O3), heat (hot air), hydrogen peroxide (H2O2), peracetic acid, other chemicals or with charge carriers produced by an electron source, in particular electrons (optionally also, on the other hand, protons or alpha particles). This should ensure as extensively as possible that, in particular, the plastics material containers produced are not contaminated to a critical degree by germs or the like when they are filled with susceptible foodstuffs. It would also be possible for other radiation such as UV, gamma or x-ray radiation to be used for the sterilization. In particular, gaseous hydrogen peroxide has been found to be particularly advantageous. If it is only intended for a cleaning to be carried out, then this could be performed with a cleaning foam.